Perhaps you should try some spelling variations:
"modified policy optimization algorithm" » "modified policy optimization algorithms", "modified policy optimisation algorithm", "modified policy estimation algorithm", "modified topology optimization algorithm"
"modified stochastic optimization algorithm" » "modified stochastic optimization algorithms", "modified stochastic optimisation algorithm", "modified stochastic estimation algorithm"

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified policy optimization algorithm") OR ("modified stochastic optimization algorithm"))~.
• Removing quotes may allow a broader search: (( modified policy optimization algorithm ) or ( modified stochastic optimization algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified policy optimization algorithm") or ("modified stochastic optimization algorithm"))*.